I've created AWS Lambda in C# using Visual Studio that returns some JSON from the API endpoint. Now I want to run that lambda locally. All the examples use AWS SAM, but they create a new function using the SAM template.
When I run the command sam local start-lambda I get an error saying that the template isn't found. So what is certain is that I need template.yaml, but I'm not sure is there a way to generate this template for existing Lambda?
Any help is appreciated!
Check out the Template Anatomy resource on the AWS documentation.
You might find this example helpful (it's greatly simplified). I use NodeJS for development, but the differences between programming languages when you're creating a SAM Template are trivial. The example is an outline for a simple Lambda function someFunction being invoked by an API Gateway (HTTP) event.
AWSTemplateFormatVersion: '2010-09-09'
Transform: 'AWS::Serverless-2016-10-31'
Description: My Serverless Application
Parameters:
# Manually define this in AWS IAM for just the services needed.
lambdaExecutionRole:
Description: 'Required. The role used for lambda execution.'
Type: 'String'
Default: 'arn:aws:iam::nnnnnnnnnnnn:role/LambdaExecutionRole'
Globals:
Function:
Runtime: nodejs10.x
# Environment:
# Variables:
# NODE_ENV: test
# DEBUG: myapp:foo
Resources:
performSomeFunction:
Type: 'AWS::Serverless::Function'
Properties:
FunctionName: performSomeFunction
Handler: lambda.someFunction
CodeUri: ./
Description: description of the function being performed
MemorySize: 256
Timeout: 60
Role:
Ref: lambdaExecutionRole
Events:
# API Gateway proxy endpoint.
ProxyApiRoot:
Type: Api
Properties:
Path: '/'
Method: ANY
ProxyApiGreedy:
Type: Api
Properties:
Path: '/{proxy+}'
Method: ANY
As you're getting started with AWS Lambda, one of the big concepts to keep in mind is how your function will be triggered. Functions are triggered by different kinds of events, and there can be many many different types of events. I tend to use API Gateway, Simple Queue Service and CloudWatch Events to trigger mine, but it entirely depends on your use case.
It turned out that you can export Lambda function, and get the generated .yaml template, which was exactly what I needed.
I have encountered this issue when trying to sam deploy my lambda function. I have found a link to the same issue here:
When using guided deploy and accepting the default options I receive a Security Constraints Not Satisfied! error. · Issue #1990 · awslabs/aws-sam-cli
However, even after reading through it and the docs, I do not understand how to fix it. Can somebody explain this to me?
This is normally happening for all those who are started with AWS SAM Hello World template and deploy without any changes or following AWS SAM tutorial. (Doesn't mean that you shouldn't start from that template or not use AWS SAM tutorial but you should add some more configurations to get rid of this message).
Here, AWS SAM is informing you that your application configures an API Gateway APIs without authorization. When you deploy the same application, AWS SAM creates a publicly available URL/API.
For getting rid of this message you need to define some access control mechanism for your API.
You can use AWS SAM to control who can access your API Gateway APIs by enabling authorization within your AWS SAM template.
example,
MyApi:
Type: AWS::Serverless::Api
Properties:
StageName: Prod
Auth:
DefaultAuthorizer: MyLambdaTokenAuthorizer
Authorizers:
MyLambdaTokenAuthorizer:
FunctionArn: !GetAtt MyAuthFunction.Arn
MyAuthFunction:
Type: AWS::Serverless::Function
Properties:
CodeUri: ./src
Handler: authorizer.handler
Runtime: nodejs12.x
The above snippet is an example of an authorization mechanism called Lambda Authorizer. There are some other mechanisms too. Like, IAM Permissions, API Keys, etc.
You can find more information about these authorizations from following link
https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-controlling-access-to-apis.html
I describe existing AWS Lambda function in CloudFormation template and I face with the next issue. In our Lambda we configured few test events which helps us to verify some usecases (I mean functionality from the screenshot below).
But I don't see any abilities to add these test events to the CloudFormation template. AWS documentation don't help me with that. Is that possible at all or are there any workarounds how to export and import Lambda function test events?
Lambda test functionality is available only in the UI console, You can use Cloudformation Custom Resource to invoke a function from a cloudformation template. Resource properties allow AWS CloudFormation to create a custom payload to send to the Lambda function.
Sample code:
Resources:
EnableLogs:
Type: Custom::EnableLogs
Version: '1.0'
Properties:
ServiceToken: arn:aws:lambda:us-east-1:acc:function:rds-EnableRDSLogs-1O6XLL6LWNR5Z
DBInstanceIdentifier: mydb
the event parameter provides the resource properties. ex:
event['ResourceProperties']['DBInstanceIdentifier']
I'm working with AWS API Gateway and AWS Lambda. Often I face this type of error message when attempt to deploy API. The error message says to select a deployment stage. But I still selecting and trying to deploy! but same error occur!
In this API I have multiple resources with multiple methods. Previously I succeed to deploy this same API with the same way. But now I can't deploy it.
Please anyone help me to fix it. For addition: I don't use AWS CLI tool, just use AWS web dashboard.
I talked with customer service center of AWS. The problem was:
In this API there was an unintegrated method. Suppose there are a resource image and I create a POST method for this resource. But I forgot to integrate it to any AWS Lambda Function or HTTP. So the API cannot be deployed.
If the method is unnecessary then delete the method. OR you can integrate it as Mock endpoint. You can change this endpoint anytime.
Note: For this unintegration problem AWS gives this type of wrong error message. They should update their message to save developer's time.
I was getting same error but when creating API using CloudFormation.
It turned out that in my AWS::ApiGateway::Deployment resource, I needed to include DependsOn attribute that "depends" on all my API methods.
For example, when building API with two AWS::ApiGateway::Method resources, AWS::ApiGateway::Deployment needs to depend on both these methods:
MyFirstApiMethod:
Type: AWS::ApiGateway::Method
Properties:
<your properties>
MySecondApiMethod:
Type: AWS::ApiGateway::Method
Properties:
<your properties>
MyDeployment:
Type: AWS::ApiGateway::Deployment
DependsOn: [MyFirstApiMethod, MySecondApiMethod] # <-- REQUIRED
Properties:
RestApiId: !Ref MyRestApi
Without the DependOn attribute on all the API methods, CloudFormation may be
creating them after the deployment resource, resulting in No integration defined for method error.
If you have another resource which is not completed to configuration it will read as well. In short, if you haven't given them a lambda function, the api itself is not allowed to be deployed until you finish the rest.
I encountered the same error with deploying via Terraform. The reason was I defined an IAM role for my API and I didn't include the role resource to triggers when deploying the API. Just make sure all resources that are defined before deploying are included in triggers.
Just integrate Lambda function in every method you created.
Make sure every resource and method is configured properly.
Let's say your api-gateway is hierarchy is like:
/
R1
R2
M1
M2
R3
M3
so every resource(R1,R2,R3) and every method(M1,M2,M3) should be configured properly.
I deployed using CDK with --no-rollback (this should work for any cloudformation though)
In my case, the API was created and I could inspect it in the AWS Console, and only the "AWS::ApiGateway::Deployment" failed to create. It turns out I had a bad value for service attribute (I was using StepFunctions, which was not working)
THEN I see that I have a dangling resouce/method that is broken - so my deployment was failing due to garbage in AWS, not my CDK/template.
When I run CloudFormation deploy using a template with API Gateway resources, the first time I run it, it creates and deploys to stages. The subsequent times I run it, it updates the resources but doesn't deploy to stages.
Is that behaviour as intended? If yes, how'd I get it to deploy to stages whenever it updates?
(Terraform mentions a similar issue: https://github.com/hashicorp/terraform/issues/6613)
Seems like there is no way to easily create a new Deployment whenever one of your Cloudformation Resources changes.
One way to work around that would be to use a Lambda-backed Custom Resource (see http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/template-custom-resources.html).
The Lambda should create the new Deployment, only if one of your Resources has been updated. To determine if one of your Resources has been updated,
you will probably have to implement custom logic around this API call: http://docs.aws.amazon.com/AWSCloudFormation/latest/APIReference/API_DescribeStackEvents.html
In order to trigger updates on your Custom Resource, I suggest you supply a Cloudformation Parameter that will be used to force an update of your Custom Resource (e.g. the current time, or a version number).
Note that you will have to add a DependsOn clause to your Custom Resource that will include all Resources relevant to your API. Otherwise, your deployment might be created before all your API Resources are updated.
Hope this helps.
When your template specifies a deployment, CloudFormation will create that deployment only if it doesn't already exist. When you attempt to run it again, it observes that the deployment still exists so it won't recreate it, thus no deployment. You need a new resource id for the deployment so that it will create a new deployment. Read this for more information: https://currentlyunnamed-theclassic.blogspot.com/2018/12/mastering-cloudformation-for-api.html
CloudFormation in Amazon's words is:
AWS CloudFormation takes care of provisioning and configuring those resources for you
http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/Welcome.html
Redeployment of APIs is not a provisioning task... It is a promotion activity which is part of a stage in your software release process.
AWS CodePipeline is a continuous delivery service you can use to model, visualize, and automate the steps required to release your software.
http://docs.aws.amazon.com/codepipeline/latest/userguide/welcome.html
CodePipeline also supports execution of Lambda functions from Actions in the pipeline. So, as advised before, create a Lambda function to deploy your API but call it from Codepipeline instead of CloudFormation.
Consult this page for details:
http://docs.aws.amazon.com/codepipeline/latest/userguide/actions-invoke-lambda-function.html
I was using above approach but it looks to complicated to me just to deploy API gateway. If we are changing name of the resources then it takes time to delete and recreate the resources which increases down time for you application.
I'm following below approach to deploy API gateway to the stage using AWS CLI and it is not affecting the deployment with Cloudformation stack.
What I'm doing is, running below AWS CLI command after deployment is completed for API Gateway. It will update the existing stage with latest updates.
aws apigateway create-deployment --rest-api-id tztstixfwj --stage-name stg --description 'Deployed from CLI'
The answer here is to use the AutoDeploy property of the Stage:
Stage:
Type: AWS::ApiGatewayV2::Stage
Properties:
StageName: v1
Description: 'API Version 1'
ApiId: !Ref: myApi
AutoDeploy: true
Note that the 'DeploymentId' property must be unspecified when using 'AutoDeploy'.
See documentation, here: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-apigatewayv2-stage.html
From the blogspot post linked by TheClassic (best answer so far!), you have to keep in mind that if you aren't generating your templates with something that can insert a valid timestamp in place of $TIMESTAMP$, you must update that manually with a time stamp or otherwise unique ID. Here is my functional example, it successfully deletes the existing deployment and creates a new one, but I will have to update those unique values manually when I want to create another change set:
rDeployment05012019355:
Type: AWS::ApiGateway::Deployment
DependsOn: rApiGetMethod
Properties:
RestApiId:
Fn::ImportValue:
!Sub '${pApiCoreStackName}-RestApi'
StageName: !Ref pStageName
rCustomDomainPath:
Type: AWS::ApiGateway::BasePathMapping
DependsOn: [rDeployment05012019355]
Properties:
BasePath: !Ref pPathPart
Stage: !Ref pStageName
DomainName:
Fn::ImportValue:
!Sub '${pApiCoreStackName}-CustomDomainName'
RestApiId:
Fn::ImportValue:
!Sub '${pApiCoreStackName}-RestApi'
I may be late, but here are the options which which you do a redeployment if a API resources changes, may be helpful to people who still looking for options -
Try AutoDeploy to true. If you are using V2 version of deployment. Note that you need to have APIGW created through V2. V1 and V2 are not compatible to each other. https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-apigatewayv2-stage.html#cfn-apigatewayv2-stage-autodeploy
Lambda backed custom resource, Lambda inturn call createDeployment API - https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/template-custom-resources.html
CodePipeline that has an action that calls a Lambda Function much like the Custom Resource would - https://docs.aws.amazon.com/codepipeline/latest/userguide/actions-invoke-lambda-function.html
SAM(Serverless Application Model) follows a similar syntax to CloudFormation which simplifies the resource creation into abstractions and uses those to build and deploy a normal CloudFormation template. https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/what-is-sam.html
If you are using any abstraction layer to cloudformation like Sceptre, you can have a hook to call createDeployment after any-update to the resource https://sceptre.cloudreach.com/2.3.0/docs/hooks.html
I gone with third option since I kept using Sceptre for Cloudformation deployment. Implementing hooks in sceptre is easy as well.
Reading through this article, I did not come to a conclusion right away, as the information here is stretched through multiple sources. I try to sum up all the findings from here (and linked source) as my personal testing to help others avoid the hunt.
Important to know is that each API always has a dedicated URL. The associated stages only get a separate suffix. Updating the deployment does not change the URL, recreating the API does.
API
├─ RestAPI (incl. Resource, Methods etc)
├─ Deployment
├─ Stage - v1 https://6s...com/v1
├─ Stage - v2 https://6s...com/v2
Relation stage and deployment:
To deploy AWS API Gateway through CloudFormation (Cfn) you need a RestApi-Cfn-Resource and a Deployment-Cfn-Resource. If you give the Deployment-Resource a stage name, the deployment automatically creates a deployment on top of the "normal" creation. If you leave this out, the API is created without any stage. Either way, if you have a deployment, you can add n-stages to a deployment by linking the two, but a stage and its API always has only one deployment.
Updating simple API:
Now if you want to update this "simple API" just consisting of a RestAPI plus a deployment you face the issue, that if the deployment has a stage name - it can not be updated as it already "exists". To detect that the deployment has to be updated in the first place, you have to either add a timestamp or hash to the deployment resource name in CloudFormation else there is even no update triggered.
Solving the deployment update:
To now enable updating the deployment, you have to split deployment and stage up into separate Cfn-Resources. Meaning, you remove the stage name from the Deployment-Cfn-Resource and create a new Stage-Cfn-Resource which references the deployment resource. This way you can update the deployment. Still, the stage - the part you reference via URL - is not automatically updated.
Propagating the update from the deployment to your stages:
Now that we can update the deployment - aka the blueprint of the API - we can propagate the change to its respective stage. This step AS OF MY KNOWLEDGE is not possible using CloudFormation. Therefore, to trigger the update you either need to add a "custom resource" our you do it manually. Other "none" CloudFormation ways are summed up by #Athi's answer above, but no solution for me as I want to limit the used tooling.
If anybody has an example for the Lambda update, please feel free to ping me - then I would add it here. The links I found so far only reference a plain template.
I hope this helped others understanding the context a bit better.
Sources:
Problem description with Cfn-template, 2
Adding timestamp to deployment resource, 2
Using CodePipeline as a solution
Related question and CLI update answer
Related terraform issue
Related AWS forum thread
This worked for me :
cfn.yml
APIGatewayStage:
Type: 'AWS::ApiGateway::Stage'
Properties:
StageName: !Ref Environment
DeploymentId: !Ref APIGatewayDeployment$TIMESTAMP$
RestApiId: !Ref APIGatewayRestAPI
Variables:
lambdaAlias: !Ref Environment
MethodSettings:
- ResourcePath: '/*'
DataTraceEnabled: true
HttpMethod: "*"
LoggingLevel: INFO
MetricsEnabled: true
DependsOn:
- liveLocationsAPIGatewayMethod
- testJTAPIGatewayMethod
APIGatewayDeployment$TIMESTAMP$:
Type: 'AWS::ApiGateway::Deployment'
Properties:
RestApiId: !Ref APIGatewayRestAPI
DependsOn:
- liveLocationsAPIGatewayMethod
- testJTAPIGatewayMethod
bitbucket-pipelines.yml
script:
- python3 deploy_api.py
deploy_api.py
import time
file_name = 'infra/cfn.yml'
ts = str(time.time()).split(".")[0]
print(ts)
with open(file_name, 'r') as file :
filedata = file.read()
filedata = filedata.replace('$TIMESTAMP$', ts)
with open(file_name, 'w') as file:
file.write(filedata)
========================================================================
Read this for more information: https://currentlyunnamed-theclassic.blogspot.com/2018/12/mastering-cloudformation-for-api.html
If you have something to do the $TIMESTAMP$ replacement, I'd probably go with that as it's cleaner and you don't have to do any manual API Gateway management.
I have found that the other solutions posted here mostly do the job with one major caveat - you can't manage your Stage and Deployment separately in CloudFormation because whenever you deploy your API Gateway, you have some sort of downtime between when you deploy the API and when the secondary process (custom resource / lambda, code pipeline, what have you) creates your new deployment. This downtime is because CloudFormation only ever has the initial deployment tied to the Stage. So when you make a change to the Stage and deploy, it reverts back to the initial deployment until your secondary process creates your new deployment.
*** Note that if you are specifying a StageName on your Deployment resource, and not explicitly managing a Stage resource, the other solutions will work.
In my case, I don't have that $TIMESTAMP$ replacement piece, and I needed to manage my Stage separately so I could do things like enable caching, so I had to find another way. So the workflow and relevant CF pieces are as follows
Before triggering the CF update, see if the stack you're about to update already exists. Set stack_exists: true|false
Pass that stack_exists variable in to your CF template(s), all the way down to the stack that creates the Deployment and Stage
The following condition:
Conditions:
StackExists: !Equals [!Ref StackAlreadyExists, "True"]
The following Deployment and Stage:
# Only used for initial creation, secondary process re-creates this
Deployment:
DeletionPolicy: Retain
Type: AWS::ApiGateway::Deployment
Properties:
Description: "Initial deployment"
RestApiId: ...
Stage:
Type: AWS::ApiGateway::Stage
Properties:
DeploymentId: !If
- StackExists
- !Ref AWS::NoValue
- !Ref Deployment
RestApiId: ...
StageName: ...
Secondary process that does the following:
# looks up `apiId` and `stageName` and sets variables
CURRENT_DEPLOYMENT_ID=$(aws apigateway get-stage --rest-api-id <apiId> --stage-name <stageName> --query 'deploymentId' --output text)
aws apigateway create-deployment --rest-api-id <apiId> --stage-name <stageName>
aws apigateway delete-deployment --rest-api-id <apiId> --deployment-id ${CURRENT_DEPLOYMENT_ID}
Use SAM
AWS::Serverless::Api
This does the deployment for you when it does the Transformation